CN104894187A

CN104894187A - Technology for preparing xylooligosaccharides from wheat straws

Info

Publication number: CN104894187A
Application number: CN201410081205.7A
Authority: CN
Inventors: 马春萍
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-03-06
Filing date: 2014-03-06
Publication date: 2015-09-09

Abstract

The invention discloses a technology for preparing xylooligosaccharides from wheat straws, and belongs to the food processing field. The technology comprises the steps of wheat straw pretreatment, boiling, enzymatic hydrolysis, concentration, decoloring, desalting and vacuum secondary concentration. Diluted alkali treatment and diluted acid treatment are sequentially carried out according to the acid and alkali resistance characteristics of xylooligosaccharides, and are combined to well remove other substances in the wheat straws, increase the active surface of the xylooligosaccharides and facilitate an enzymatic hydrolysis reaction, and the obtained xylooligosaccharides are based on xylobiose and xylotriose, and are highly pure; and the above raw material has a low price, can be locally obtained, and can be conveniently processed, so the technology has the advantages of cost saving, changing of wastes into valuables, and environment protection.

Description

A kind of wheat straw xylo-oligosaccharide preparation technology

Technical field

The invention belongs to food processing field, be specifically related to a kind of wheat straw xylo-oligosaccharide preparation technology.

Background technology

The stalk of wheat is called wheat straw, and before China eighties in 20th century, peasant is very abundant to the utilization of stalk, is seldom directly slatterned.Such as in Gansu, wheat straw is dried storage by people, can be used to ignite, fills out a heatable brick bed, make the housewares such as broom, and pasture, place mat domestic animal circle, heap are made compost and gone back field etc.But recent two decades comes, and because industrialization is popularized, rural area is reduced the use of stalk, a large amount of stalk be processed in order to a serious social concern, a lot of local peasant direct burning straw in the fields, produces cigarette ash, cause atmospheric pollution, even cause aircraft cannot Normal Take-Off And Landing.

Containing abundant xylan in wheat straw, can be used as the raw material producing xylo-oligosaccharide.Xylo-oligosaccharide also known as wood oligose, 45% of the suitable sweetness of cane sugar of solid xylo-oligosaccharide, soluble in water, provide energy almost nil to human body, safety non-toxic.

Xylo-oligosaccharide is a kind of new and effective functional oligose, and added value is high, is widely used, as food, drink, medicine, healthcare products and for feed, therefore, and good market prospect.

Summary of the invention

Technical problem to be solved by this invention is to provide a kind of wheat straw xylo-oligosaccharide preparation technology.

To achieve these goals, the present invention is achieved by the following technical solutions:

A kind of wheat straw xylo-oligosaccharide preparation technology, the concrete steps comprised are:

(1) wheat straw is removed impurity, clean up, pulverize after drying, cross 60-80 mesh sieve, for subsequent use;

(2) the wheat straw powder after sieving fully is immersed 0.2-0.5% sodium hydroxide solution, stir 3-4h in 30-50 DEG C, filtering separation, obtains filter residue;

(3) filter residue fully immerses 0.5-1.5% dilution heat of sulfuric acid, and stir 3-4h in 50-65 DEG C, filtering separation, obtains secondary filter residue;

(4) after secondary filter residue being washed to neutrality, add 6-10 times of water gaging, in 120 DEG C of boiling 1-2h, refilter to obtain boiling slag, wash with water 1-2 time, drain and be xylan raw material;

(5) xylan raw material and zytase are dropped into enzymatic vessel, be deployed into containing xylan 15-20g/L with distilled water, the mixture of zytase 1-2%, 4-8h is reacted under temperature is 45-60 DEG C of condition, rapid temperature increases is to 90-105 DEG C, and insulation 30-60min, obtains thick oligosaccharide solution;

(6) thick oligosaccharide solution is placed in whizzer centrifugal 10-20min under 3000r/min condition, gets supernatant liquor, concentrated 4-6 doubly, obtains oligosaccharide solution;

(7) oligosaccharide solution proceeded in decolouring still, adjust pH to 5, add the craboraffin of 1.5% amount of solution, decolour 30-45min at 55 DEG C, filters, obtain filtrate;

(8) use in sodium hydroxide and destainer extremely neutrality, be then placed in electrodialysis unit desalination;

(9) at 70 DEG C, negative-pressure vacuum concentrates, and obtains the liquid oligomers sugar product of 40-70%.

In above-mentioned wheat straw xylo-oligosaccharide preparation technology, the volume of employing dilution heat of sulfuric acid is 5-10 times of wheat straw opaque amount.

In above-mentioned wheat straw xylo-oligosaccharide preparation technology, the volume of employing sodium hydroxide solution is 6-8 times of wheat straw opaque amount.

In above-mentioned wheat straw xylo-oligosaccharide preparation technology, after craboraffin decolouring, filter residue is washed 1-2 time, merging filtrate and washing lotion, carry out ultrafiltration and can remove impurity in de-liquid further.

In above-mentioned wheat straw xylo-oligosaccharide preparation technology, can desalination further with zwitterion resin after electrodialysis desalination.

In above-mentioned wheat straw xylo-oligosaccharide preparation technology, gained oligose product adds vehicle and sprays into solid xylo-oligosaccharide product.

Beneficial effect of the present invention:

Wheat straw is cheap, turns waste into wealth, and protection of the environment is gathered materials on the spot, and is convenient to processing, saves cost; Acidproof according to xylo-oligosaccharide, alkaline-resisting feature, first alkaline purification, rear acid treatment, both combine other materials better deviate from wheat straw, increase xylanase activity surface, are beneficial to enzyme digestion reaction, the oligose obtained based on xylo-bioses and xylotriose, good product purity.

Embodiment

Set forth further in conjunction with the embodiments, the present invention is not construed as limiting.

Embodiment 1

Clean wheat straw is pulverized, after crossing 80 mesh sieves, abundant immersion 0.2% sodium hydroxide solution, 4h is stirred in 30 DEG C, filtering separation, filter residue fully immerses 0.5% dilution heat of sulfuric acid, 3h is stirred in 50 DEG C, filtering separation, obtain secondary filter residue, after being washed to neutrality, add 6 times of water gagings, in 120 DEG C of boiling 2h, refilter to obtain boiling slag, wash 1-2 time, drain rear and zytase input enzymatic vessel, be deployed into containing xylan 15g/L with distilled water, the mixture of zytase 1%, 8h is reacted under temperature is 45 DEG C of conditions, rapid temperature increases to 90 DEG C, insulation 60min, be placed in whizzer centrifugal 10min under 3000r/min condition, get supernatant liquor, concentrated 6 times, obtain oligosaccharide solution, proceed in decolouring still, adjust pH to 5, add the craboraffin of 1.5% amount of solution, decolour 30min at 55 DEG C, filter, with extremely neutral with destainer in sodium hydroxide, then electrodialysis unit desalination is placed in, at 70 DEG C, negative-pressure vacuum concentrates, obtain the liquid oligomers sugar product of 50%.

Embodiment 2

Clean wheat straw is pulverized, after crossing 70 mesh sieves, abundant immersion 0.3% sodium hydroxide solution, 3.5h is stirred in 40 DEG C, filtering separation, filter residue fully immerses 1% dilution heat of sulfuric acid, 3.5h is stirred in 60 DEG C, filtering separation, obtain secondary filter residue, after being washed to neutrality, add 8 times of water gagings, in 120 DEG C of boiling 1.5h, refilter to obtain boiling slag, wash 1-2 time, drain rear and zytase input enzymatic vessel, be deployed into containing xylan 18g/L with distilled water, the mixture of zytase 1.5%, 6h is reacted under temperature is 50 DEG C of conditions, rapid temperature increases to 100 DEG C, insulation 45min, be placed in whizzer centrifugal 15min under 3000r/min condition, get supernatant liquor, concentrated 5 times, obtain oligosaccharide solution, proceed in decolouring still, adjust pH to 5, add the craboraffin of 1.5% amount of solution, decolour 40min at 55 DEG C, filter, with extremely neutral with destainer in sodium hydroxide, then electrodialysis unit desalination is placed in, at 70 DEG C, negative-pressure vacuum concentrates, obtain the liquid oligomers sugar product of 60%.

Embodiment 3

Clean wheat straw is pulverized, after crossing 60 mesh sieves, abundant immersion 0.5% sodium hydroxide solution, 3h is stirred in 50 DEG C, filtering separation, filter residue fully immerses 1.5% dilution heat of sulfuric acid, 3h is stirred in 60 DEG C, filtering separation, obtain secondary filter residue, after being washed to neutrality, add 10 times of water gagings, in 120 DEG C of boiling 1h, refilter to obtain boiling slag, wash 1-2 time, drain rear and zytase input enzymatic vessel, be deployed into containing xylan 20g/L with distilled water, the mixture of zytase 2%, 4h is reacted under temperature is 60 DEG C of conditions, rapid temperature increases to 105 DEG C, insulation 30min, be placed in whizzer centrifugal 20min under 3000r/min condition, get supernatant liquor, concentrated 4 times, obtain oligosaccharide solution, proceed in decolouring still, adjust pH to 5, add the craboraffin of 1.5% amount of solution, decolour 30min at 55 DEG C, filter, with extremely neutral with destainer in sodium hydroxide, then electrodialysis unit desalination is placed in, at 70 DEG C, negative-pressure vacuum concentrates, obtain the liquid oligomers sugar product of 70%.

Claims

1. a wheat straw xylo-oligosaccharide preparation technology, is characterized in that: the concrete steps comprised are:

(2) the wheat straw powder after sieving fully is immersed sodium hydroxide solution, stir 3-4h in 30-50 DEG C, filtering separation, obtains filter residue;

(3) filter residue fully immerses dilution heat of sulfuric acid, and stir 3-4h in 50-65 DEG C, filtering separation, obtains secondary filter residue;

(5) xylan raw material and zytase are dropped into enzymatic vessel, be deployed into mixture, under temperature is 45-60 DEG C of condition, reacts 4-8h with distilled water, rapid temperature increases is to 90-105 DEG C, and insulation 30-60min, obtains thick oligosaccharide solution;

(7) oligosaccharide solution proceeded in decolouring still, adjust pH to 5, add craboraffin, decolour 30-45min at 55 DEG C, filters, obtain filtrate;

2. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: the concentration of sodium hydroxide solution is (2) 0.2-0.5%, and volume is 6-8 times of wheat straw opaque amount.

3. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: the dilution heat of sulfuric acid concentration is (3) 0.5-1.5%, and volume is 5-10 times of wheat straw opaque amount.

4. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: the mixture is (5) containing xylan 15-20g/L, zytase 1-2%.

5. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: (7), craboraffin parts by weight are 1.5% of amount of solution.

6. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: (7) after craboraffin decolouring, washed 1-2 time by filter residue, merging filtrate and washing lotion, carries out ultrafiltration and can remove impurity in de-liquid further.

7. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: can desalination further with zwitterion resin after electrodialysis desalination (8).

8. a kind of wheat straw xylo-oligosaccharide preparation technology as claimed in claim 1, is characterized in that: (9), gained oligose product adds vehicle and sprays into solid xylo-oligosaccharide product.